The present invention is directed to an optical cable comprising a longitudinally extending carrier member having outwardly accessible chambers which are helically wrapped on said member and extend in a longitudinal direction, said chambers serving for the acceptance of light waveguides, whereby the chambers are separated from one another by webs.
A cable having a longitudinally extending carrier having outwardly extending chambers, which extend helically in the longitudinal direction and are separated by webs, is disclosed in German Patent No. 24 49 439. The chambers of this patent have a profile that expands outwardly in a sector fashion and the webs separating adjacent chambers have a substantially constant thickness.
In many applications, it is necessary to provide chamber profiles other than exactly sector-shaped chamber profiles. For example, chambers having a rectangular cross section or profile are desirable, for instance when stacks of small bands are placed in these chambers. For examples, stacks of light waveguide arrangements wherein a respective plurality of light waveguides are arranged next to one another in the fashion of ribbon cable and these cables are arranged as a stack of cables. Such a stack of small bands has an approximately rectangular contour or shape along the outside and, accordingly, the cross section of the chamber should also be designed approximately rectangularly. On the other hand, ribbon-shaped elements can easily dislocate relative to one another, twist, turn and, thus, suffer additional local attenuations over the entire cable length on an average. It is, thus, expedient for a stack of ribbon-shaped elements to be limited from lateral play in a defined fashion.
In chamber cross sections that are not exactly sector-shaped but are rectangular profiles, problems will occur that the webs comprise unequal material cross sections. For example, the thinner wall thickness will occur closer to the axis of the carrier and the webs will taper with the greater wall thickness turning towards the radial outer portion of the carrier. When a carrier member containing rectangular chambers is manufactured by extruding, undesirable deformation of the chamber profile will occur during cooling as a consequence of the non-uniform distribution of material in the webs.